Usually the electric and magnetic fields associated with lightning have been computed by assuming the lightning current to be contained in a straight vertical channel of negligible cross section above a flat perfectly conducting plane. Such a model, which does not take into account that real lightning is characterized by tortuosity and branching, is not able to justify the fine structure of the fi...
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With continually increasing operating frequencies, the analysis of electromagnetic interference (EMI)-related effects is becoming an important issue for high-speed designs. An algorithm is presented for fast analysis of radiation and incident field coupling effects in high-speed circuits. The proposed technique provides an efficient means for combining the solutions from full-wave field solvers su...
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The temperature rises in the human eye for plane wave exposures are investigated in the frequency range between 600 MHz and 6 GHz, which covers the hot spot frequency range. As a first step, the specific absorption rates (SARs) are calculated with the use of the finite-difference time-domain (FDTD) method and the mechanism of hot-spot formation is discussed. Then the temperature rises in the human...
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As the density of transmitters from mobile telecommunication systems continues to increase there is a greater risk of electromagnetic compatibility (EMC) problems due to the ensemble electromagnetic field from multiple mobile handsets. An analysis of the characteristics of the threat field from multiple handsets is presented allowing prediction of the statistics of the ensemble field. A measuremen...
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A generalized mathematical procedure is developed for investigating a TEz-polarized plane wave penetration through two-dimensional (2-D) multilayered cylindrical cavity-backed apertures. The mathematical treatment is based on the direct integral equation technique combined with the Galerkin's procedure. Both the near- and far-zone field solutions to such a multiple coupling system are o...
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The resonance suppression for the electromagnetic shielding enclosure is theoretically investigated. A simple model of a double-layered spherical shell with a plane-wave illumination is assumed. When a spherical shell made of conductive dielectrics is covered with a thin metal layer, the conductivity of the dielectrics has an optimum value which minimizes the Q-factor at the fundamental resonant f...
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There have been a number of reports of electromagnetic interference (EMI) on electronic medical equipment caused by mobile telecommunication systems. In Japan, the use of the personal handy-phone system (PHS) has greatly expanded within urban areas, PHS handsets transmit EM signals at a frequency of 1.9 GHz and have a peak radiated power of 80 mW. This power level is lower than that of other mobil...
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Biological studies and, in particular, epidemiological ones require the estimation of the RF exposure induced by a mobile phone. Due to the different techniques used by global system mobile (GSM) and digital communication system (DCS) such as power control and discontinuous transmission, the power emitted by a handset is largely variable. As these parameters depend on the environment and the netwo...
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Interference produced in hearing aids by the pulsed RF signal from digital wireless phones has become an increasingly important issue to wireless phone manufacturers and service providers, hearing aid manufacturers and users, and government regulatory agencies. Development and validation of a comprehensive model of the interaction would greatly benefit the efforts to achieve mutual electromagnetic...
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The proliferation of communication systems used in and around man-made structures has resulted in a growing need to determine the reflection and transmission properties of various commonly used building materials at radio frequencies typically used in businesses and residential environments. This paper describes the calculation of reflection and transmission coefficients for reinforced concrete wa...
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The utility of the minimum-scattering antenna model in describing the mutual coupling between two L-band aircraft blade antennas is examined. The communication and sensor requirements of many aircraft, particularly those used by the military, frequently necessitate antennas being placed in close proximity to one another. For such cases, the relatively simple minimum-scattering antenna model provid...
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We present the work carried out in the SOBITS project executed within the framework of the European Measurement and Testing program. The goal of the project was to compare different methods for characterization of the shielding performance of board-to-backplane and backplane-to-cable connectors used in telecommunication and computer systems. Four measurement methods have been selected. Dedicated t...
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The uncertainty in the current waveform measurement of an electrostatic discharge (ESD) generator is evaluated. The measurands are the current amplitude and the rise time of the output current waveform of the ESD generator. An intuitively simple model is proposed to evaluate the uncertainty in the current amplitude measurement. Type A and Type B evaluations for all contributions to the measurement...
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This article treats pickup and scattering by a single wire in free space or over a ground plane. The wire may be uniform or nonuniform and infinite or finite. We only treat the case where wire radius is so small compared to a wavelength and the other problem dimensions that scattering by the wire is independent of azimuth. Solutions based directly on Maxwell's equations are compared with solutions...
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The issue of finding a new electromagnetic interference (EMI) measurement detector with proper weighting properties for the effect of disturbances on digital communication services is of great importance for the development of future emission standards. We investigate the root-mean-square (RMS) detector as a possible candidate for future emission measurements. This investigation is done for type o...
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In this paper, two efficient algorithms for the steady-state scattering responses of a nonlinearly loaded antenna and antenna array in the frequency domain are studied. One is the reflection algorithm (RA), and the other is the inexact Newton approach (INA). The analysis is equivalent to a nonlinear circuit problem with the circuit parameters of antenna element obtained by the moment method. This ...
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This paper deals with the broad-band modeling of a realistic power converter shield used in an electric vehicle. To validate such a model, comparisons between computation and measurements are required. As it is not practical to characterize experimentally the true radiation of a power converter through its enclosure, a reciprocal approach has been defined in which the enclosure is illuminated by a...
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A novel structure is investigated for the improvement of tri-plate line (TPL) performance. Based on experience in the design of horn antennas, we introduce corrugations of the transition section of the TPL in order to achieve better field uniformity and to reduce the return loss. A corrugated transition waveguide may be viewed as the cascade of bifurcated metal waveguides. We employed the building...
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Two new concepts applicable to cylindrical generalized screens are introduced: standard responses and standard excitations. The standard responses allow the description of any current and charge distribution on the screen. For a given generalized screen's cross-section, they can be derived from the complex potential of a simple electrostatic problem. The standard excitations are electromagnetic (E...
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